The overall goal of this project is an indepth analysis of the thymus derived lymphocyte and its products. The basic approach is to use continuously propagable T cell lines which express specificity for individual antigens. Highly purified, functionally characterized, antigen sensitized T cells will be fused with extensively analyzed, cloned T cell lymphomas to make T cell hybrids. Lymphoma parents will be chosen which most nearly approximate the differentiated state of the primary T cell. In other experiments purified T cells will be treated with antigen and T cell growth factor. Antigen-specific continuous T cell lines will be used as source material to analyze the parameters which regulate T cell recognition of antigen. T cell lines will be used as source material for molecular analysis of lymphokines and T cell receptors by SDS-polyacrylamide gel electrophoresis, column chromatography, and two-dimensional gel electrophoresis.